CN109779588B - Steam injection, leakage-proof back flushing and production integrated tubular column for thermal production well - Google Patents

Steam injection, leakage-proof back flushing and production integrated tubular column for thermal production well Download PDF

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Publication number
CN109779588B
CN109779588B CN201711111932.3A CN201711111932A CN109779588B CN 109779588 B CN109779588 B CN 109779588B CN 201711111932 A CN201711111932 A CN 201711111932A CN 109779588 B CN109779588 B CN 109779588B
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wall
steam injection
sealing plug
conical surface
sealing
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CN109779588A (en
Inventor
李常友
陈伟
梅明霞
张学超
宋清新
王冰
邬彬
杨军
杨胜利
许霞
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China Petroleum and Chemical Corp
Sinopec Research Institute of Petroleum Engineering Shengli Co
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China Petroleum and Chemical Corp
Sinopec Research Institute of Petroleum Engineering Shengli Co
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/10Geothermal energy

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Abstract

The invention discloses an integrated pipe column for steam injection, leakage prevention and reverse flushing of a thermal production well, which comprises an oil pipe, a lifting pump, a downhole multifunctional control valve and a sealing plug which are sequentially connected from top to bottom, wherein the outer wall of the sealing plug is sleeved with a sealing cylinder and a downhole positioning tool, the lower end of the sealing cylinder is connected with the upper end of the downhole positioning tool through a threaded nipple, the outer wall of the downhole positioning tool is provided with a positioning locking claw, the lower end of the downhole positioning tool is fixed on the sealing plug through a shear pin, the outer wall of the positioning locking claw is provided with a horseshoe, the horseshoe of the positioning locking claw is buckled with the horseshoe inside a packer for retaining the well in a corresponding manner, and the lower end of the packer is connected with a sand filtering pipe. The invention solves the problems that three operations are needed for steam injection, back flushing and production, time and labor are wasted, and the temperature of an oil layer is reduced due to back flushing of the existing steam injection thermal recovery well, thereby ensuring the steam injection effect.

Description

Steam injection, leakage-proof back flushing and production integrated tubular column for thermal production well
Technical Field
The invention relates to the field of production pipe columns of thermal production wells in oil fields, in particular to an integrated pipe column for steam injection, leakage-proof back flushing and production of the thermal production well.
Background
And (3) flushing after the steam is injected into the thick oil thermal production well, discharging after flushing, then placing a backwashing well pipe column for backwashing operation, and then placing a production pipe column for oil production. This approach has mainly the following disadvantages: three operations are needed for steam injection, back flushing and production, the operation procedures are complicated, troublesome and high in cost, especially after high-temperature steam injection, the temperature and pressure of a shaft are high, and the operation risk is high; meanwhile, when the well is reversely washed, well entering liquid is easy to leak out and enters an oil layer just filled with the steam, and when the well entering liquid is polluted by the well entering liquid, new cold injury is caused to the stratum. In order to solve the problem, the invention particularly provides an integrated pipe column for steam injection, leakage-proof back flushing and oil extraction production. The one-pass pipe column is realized, and the steam injection, the leakage-proof anti-flushing and the oil extraction production are realized.
Through the search, the pipe columns capable of realizing steam injection, back flushing and production at the same time are found to be numerous, but the technical scheme of the whole structure is different, and the pipe columns capable of solving the problem of oil layer temperature reduction caused by back flushing of the existing steam injection thermal production well are not found.
Disclosure of Invention
The invention aims to provide an integrated pipe column for steam injection, leakage-proof back flushing and production of a thermal production well, so as to solve the problems that three operations are needed for steam injection, back flushing and production, time and labor are wasted, and the temperature of an oil layer is reduced due to back flushing of the existing steam injection thermal production well, thereby ensuring the steam injection effect.
In order to achieve the aim, the invention adopts the following technical scheme that the integrated pipe column for steam injection, leakage prevention reverse flushing and production of the thermal recovery well comprises an oil pipe, a lifting pump, a downhole multifunctional control valve and a sealing plug which are sequentially connected from top to bottom, wherein the outer wall of the sealing plug is sleeved with a sealing cylinder and a downhole positioning tool, the lower end of the sealing cylinder is connected with the upper end of the downhole positioning tool through a threaded nipple, the outer wall of the downhole positioning tool is provided with a positioning locking claw, the lower end of the downhole positioning tool is fixed on the sealing plug through a shear pin, the outer wall of the positioning locking claw is provided with a horseshoe, the horseshoe of the positioning locking claw is correspondingly buckled with the horseshoe inside a packer for leaving the well, and the lower end of the packer is connected with a sand filtering pipe.
The multifunctional downhole control valve comprises a central tube, a circulating sleeve, a baffle ring and a spring, wherein an upper conversion hole and a lower conversion hole which are radially communicated are formed in the central tube, an inner conical surface bulge is formed in the inner wall of the central tube, the upper conversion hole is formed above the inner conical surface bulge, the lower conversion hole is formed below the inner conical surface bulge, the circulating sleeve is arranged outside the central tube, the baffle ring is connected to the lower part of the circulating sleeve, the spring is arranged on the lower part of the baffle ring, and the lower end of the spring is propped against the upper end face of the sealing plug.
The center tube outer wall is provided with a limiting table, wherein the circulating sleeve is axially limited downwards relative to the limiting table, and the baffle ring is axially limited upwards relative to the limiting table.
When the baffle ring is limited on the limiting table, the circulating sleeve completely seals the upper conversion hole and the lower conversion hole, and when the circulating sleeve slides along with the downward compression spring of the baffle sleeve, the circulating sleeve only seals the lower conversion hole and releases the upper conversion hole.
And sealing rings are arranged at the inner side of the upper end of the circulating sleeve and the outer side of the limiting table.
An inner conical surface reducing hole is formed in the axial direction of the inner conical surface bulge, and a steel ball is thrown into the inner conical surface reducing hole.
The outer wall of the upper end of the sealing plug is a conical surface, the upper port of the sealing cylinder corresponds to the conical surface, and the inner wall of the sealing cylinder and the outer wall of the sealing plug are in a sealing state.
The positioning locking claw comprises a base ring and split type claws which are longitudinally and uniformly arranged on the base ring, and the horseshoe buckle is in a protruding clamping table shape and is arranged on the outer wall of the split type claw.
Compared with the prior art, the invention has the following beneficial effects:
1. the thermal production well is injected with steam, the anti-leakage and anti-flushing well and the production integrated pipe column is put into the well, and the free conversion of three working states of steam injection, anti-leakage and anti-flushing well and oil production can be realized.
2. During the back flushing operation, the flushing liquid pushes the circulating sleeve and the baffle ring compression spring of the underground multifunctional control valve, the descending channel of the oil pipe is cut off, the flushing liquid cannot enter the oil layer section, and the influence of the leakage of the flushing liquid on the steam injection effect after the steam injection is reduced.
Drawings
FIG. 1 is a schematic diagram of a thermal recovery well steam injection, leak-proof back flushing and production integrated tubular column according to the present invention;
FIG. 2 is a view showing the structure of the present invention when injecting steam;
FIG. 3 is a structural view of the invention in a back flushing operation;
fig. 4 is a structural state diagram of the oil recovery according to the present invention.
In the figure: the oil pipe 1, the lifting pump 2, the underground multifunctional control valve 3, the steel ball 4, the circulating sleeve 5, the spring 6, the sealing plug 7, the sealing cylinder 8, the underground positioning tool 9, the positioning locking claw 10, the shear pin 11, the packer 12, the sand filtering pipe 13 and the sucker rod 14.
Detailed Description
The detailed description and technical content of the present invention are described below with reference to the accompanying drawings, which are, however, only for reference and description, and are not intended to limit the present invention.
According to fig. 1 to 4, the integrated pipe column for steam injection, leakage-proof reverse flushing and production of the thermal production well comprises an oil pipe 1, a lifting pump 2, an underground multifunctional control valve 3 and a sealing plug 7 which are sequentially connected from top to bottom, wherein the outer wall of the sealing plug is sleeved with a sealing cylinder 8 and an underground positioning tool 9, the lower end of the sealing cylinder is connected with the upper end of the underground positioning tool through a threaded nipple, the outer wall of the underground positioning tool 9 is provided with a positioning locking claw 10, the lower end of the underground positioning tool is fixed on the sealing plug through a shear pin 11, the outer wall of the positioning locking claw is provided with a horseshoe, the horseshoe of the positioning locking claw is correspondingly buckled with the horseshoe inside a packer 12 for retaining the well, and the lower end of the packer is connected with a sand filtering pipe 13.
The multifunctional downhole control valve comprises a central tube, a circulating sleeve 5, a baffle ring and a spring 6, wherein an upper conversion hole and a lower conversion hole which are radially communicated are formed in the central tube, an inner conical surface bulge is formed in the inner wall of the central tube, the upper conversion hole is formed above the inner conical surface bulge, the lower conversion hole is formed below the inner conical surface bulge, the circulating sleeve is arranged outside the central tube, the baffle ring is connected to the lower part of the circulating sleeve, the spring is arranged on the lower part of the baffle ring, and the lower end of the spring is propped against the upper end face of the sealing plug.
The center tube outer wall is provided with a limiting table, wherein the circulating sleeve is axially limited downwards relative to the limiting table, and the baffle ring is axially limited upwards relative to the limiting table.
When the baffle ring is limited on the limiting table, the circulating sleeve completely seals the upper conversion hole and the lower conversion hole, and when the circulating sleeve slides along with the downward compression spring of the baffle sleeve, the circulating sleeve only seals the lower conversion hole and releases the upper conversion hole.
And sealing rings are arranged at the inner side of the upper end of the circulating sleeve and the outer side of the limiting table.
An inner conical surface reducing hole is formed in the axial direction of the inner conical surface bulge, and a steel ball 4 is thrown into the inner conical surface reducing hole.
The outer wall of the upper end of the sealing plug is a conical surface, the upper port of the sealing cylinder corresponds to the conical surface, and the inner wall of the sealing cylinder and the outer wall of the sealing plug are in a sealing state.
The positioning locking claw comprises a base ring and split type claws which are longitudinally and uniformly arranged on the base ring, and the horseshoe buckle is in a protruding clamping table shape and is arranged on the outer wall of the split type claw.
The invention relates to a concrete implementation method for a thermal production well, which comprises the following steps: after sand prevention gravel filling is completed, gravel is filled outside the sand filtering pipe 13, the whole oil sleeve annulus is filled, the sand prevention pipe column rotates forward, and the sand prevention pipe column is released to take out the service pipe column. The underground positioning tool 9, the sealing plug 7, the sealing cylinder 8, the underground multifunctional control valve 3, the lifting pump 2 and the oil pipe 1 are connected from bottom to top in sequence, the sealing cylinder is used for ensuring that the sealing plug moves up and down after the pin 11 is sheared, and simultaneously ensuring the sealing between the sealing plug and an annulus, so that steam is prevented from being leaked, the sealing cylinder 8 is in threaded connection with the underground positioning tool 9, the underground positioning tool is arranged outside the sealing plug 7, and the underground positioning tool 9 is fixed with the sealing plug 7 through the shear pin 11. The sealing cylinder 8 and the downhole positioning tool 9 are sleeved outside the sealing plug 7, and the downhole positioning tool 9 is fixed on the sealing plug through a shear pin 11. The lower part of the sealing plug 7 is inserted into the fish top of the sand control pipe column reserved well. The running sand control pipe column mainly comprises the steps of running a plug, a sand filtering pipe and a filling tool to a part needing sand control through a service tool, setting the filling tool after the filling sand control construction is finished, disconnecting the service tool from the filling tool, lifting the service tool out, and leaving the uppermost end of the well to be the sand control pipe column, namely, leaving the fish top of the well, namely, the top end of a packer 12 shown in fig. 2, wherein the packer 12 can also be the filling tool because the filling tool has the function of the packer. The outer wall of the lower part of the underground positioning tool 9 is provided with a positioning locking claw 10, the external thread of the positioning locking claw 10 is a horseshoe buckle, the horseshoe buckle at the outer side of the positioning locking claw 10 is buckled with the horseshoe buckle in the packer 12 for well retention, and the sealing cylinder 8 is fixed at the fish top of the well retention. The pipe column is pressurized downwards, the shear pins 11 are sheared off, the sealing plug 7 can move up and down, the sealing cylinder 8 ensures the sealing between the sealing plug 7 and the annular space, and steam channeling of injected steam is avoided. The injected steam enters the production interval through the upper circulation hole and the lower circulation hole of the downhole multifunctional control valve 3. And (3) flushing after the steam injection, discharging after flushing, and performing backwashing operation. The backwashed liquid is injected from the oil sleeve annulus, the liquid compresses the circulating sleeve 5, the baffle ring and the spring 6 of the underground multifunctional control valve 3, the upper circulating hole is exposed, and the liquid returns to the ground through the upper circulating hole and the oil pipe. And the backwashing operation is completed. During oil well production, the sucker rod 14 is put in, the pump valve is arranged at the lower part, oil flow can enter the oil pipe through the side flow channels of the lower circulation hole and the upper circulation hole, and the steel ball 4 can also be jacked up to enter the oil pipe, so that the oil well production can be realized.
The main advantages of the invention are mainly as follows:
1. the free conversion of three working states of steam injection, leakage-proof back flushing and oil extraction production can be realized.
2. Through the use of the pipe column and the cooperation of the pipe column and the packer, the well flushing liquid does not enter the oil layer section, and the influence of the well flushing liquid leakage after the steam injection on the steam injection effect is reduced.
The foregoing description of the preferred embodiments of the present invention is not intended to limit the scope of the invention, but rather to limit the scope of the invention to the equivalents of the claims to which the invention pertains.

Claims (6)

1. The integrated pipe column is characterized by comprising an oil pipe, a lifting pump, an underground multifunctional control valve and a sealing plug which are sequentially connected from top to bottom, wherein the outer wall of the sealing plug is sleeved with a sealing cylinder and an underground positioning tool, the lower end of the sealing cylinder is connected with the upper end of the underground positioning tool through a threaded nipple, the outer wall of the underground positioning tool is provided with a positioning locking claw, the lower end of the underground positioning tool is fixed on the sealing plug through a shear pin, the outer wall of the positioning locking claw is provided with a horseshoe, the horseshoe of the positioning locking claw is buckled with the horseshoe inside a packer for retaining the well in a corresponding manner, and the lower end of the packer is connected with a sand filtering pipe;
the underground multifunctional control valve comprises a central pipe, a circulating sleeve, a baffle ring and a spring, wherein an upper conversion hole and a lower conversion hole which are radially communicated are formed in the central pipe, an inner conical surface bulge is formed in the inner wall of the central pipe, the upper conversion hole is positioned above the inner conical surface bulge, the lower conversion hole is positioned below the inner conical surface bulge, the circulating sleeve is arranged outside the central pipe, the baffle ring is connected to the lower part of the circulating sleeve, the spring is arranged at the lower part of the baffle ring, and the lower end of the spring is propped against the upper end surface of the sealing plug;
the outer wall of the upper end of the sealing plug is a conical surface, the upper port of the sealing cylinder corresponds to the conical surface, and the inner wall of the sealing cylinder and the outer wall of the sealing plug are in a sealing state.
2. The integrated thermal recovery well steam injection, leak protection back flushing and production string of claim 1, wherein the outer wall of the central tube is provided with a limiting table, wherein the circulation sleeve is axially limited downwards relative to the limiting table, and wherein the baffle ring is axially limited upwards relative to the limiting table.
3. The integrated thermal recovery well steam injection, leak-proof back flushing and production string according to claim 1 or 2, wherein the circulation sleeve completely seals the upper conversion hole and the lower conversion hole when the baffle ring is limited on the limiting table, and only seals the lower conversion hole and releases the upper conversion hole when the circulation sleeve slides along with the downward compression spring of the baffle sleeve.
4. The integrated thermal recovery well steam injection, leak-proof back flushing and production pipe column according to claim 1 or 2, wherein sealing rings are arranged on the inner side of the upper end of the circulating sleeve and the outer side of the limiting table.
5. The integrated thermal recovery well steam injection, leak protection back flushing and production string according to claim 1 or 2, wherein an inner conical surface shrinkage cavity is formed in the axial direction of the inner conical surface bulge, and a steel ball is thrown into the inner conical surface shrinkage cavity.
6. The integrated tubular column for steam injection, leakage prevention back flushing and production of thermal recovery wells according to claim 1, wherein the positioning locking claw comprises a base ring and split type claws longitudinally and uniformly arranged on the base ring, and the horseshoe buckle is in a protruding clamping table shape and is arranged on the outer wall of the split type claw.
CN201711111932.3A 2017-11-10 2017-11-10 Steam injection, leakage-proof back flushing and production integrated tubular column for thermal production well Active CN109779588B (en)

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CN201711111932.3A CN109779588B (en) 2017-11-10 2017-11-10 Steam injection, leakage-proof back flushing and production integrated tubular column for thermal production well

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Application Number Priority Date Filing Date Title
CN201711111932.3A CN109779588B (en) 2017-11-10 2017-11-10 Steam injection, leakage-proof back flushing and production integrated tubular column for thermal production well

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CN109779588B true CN109779588B (en) 2023-06-16

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111305789B (en) * 2020-02-25 2022-05-03 中国海洋石油集团有限公司 Thermal recovery leakage-proof circulating sliding sleeve

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2506769Y (en) * 2001-07-27 2002-08-21 郑碧锁 Screen casing type ceramic sand filtering pipe
CN2611601Y (en) * 2002-05-10 2004-04-14 中国石油天然气股份有限公司 Layered quantitative steam injection pipe column
CN2646370Y (en) * 2003-10-15 2004-10-06 中国石化胜利油田有限公司采油工艺研究院 Pipe fisher capable of washing and filtering sand
CN201024941Y (en) * 2007-04-04 2008-02-20 大港油田集团有限责任公司 Sifting tube suspender
CN202745784U (en) * 2012-07-26 2013-02-20 中国石油天然气股份有限公司 Slip type gas lift fishing tool for downhole choke
CN103470229A (en) * 2013-09-24 2013-12-25 山东大学 Sand protection matching pipe string for high-throughput sand filter pipe
CN104213888A (en) * 2014-07-28 2014-12-17 中国石油化工股份有限公司 Down-hole steam injection string of thick-oil thermal production well
CN104481491A (en) * 2014-12-09 2015-04-01 中国石油集团川庆钻探工程有限公司 Circulation control type casing sliding sleeve closing tool
CN106555574A (en) * 2015-09-25 2017-04-05 中国石油化工股份有限公司 Sand control, steam injection integrated apparatus and method
CN207485415U (en) * 2017-11-10 2018-06-12 中国石油化工股份有限公司 A kind of thermal production well steam injection, lost circulation prevention anti-flushing well and production integration tubing string

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2506769Y (en) * 2001-07-27 2002-08-21 郑碧锁 Screen casing type ceramic sand filtering pipe
CN2611601Y (en) * 2002-05-10 2004-04-14 中国石油天然气股份有限公司 Layered quantitative steam injection pipe column
CN2646370Y (en) * 2003-10-15 2004-10-06 中国石化胜利油田有限公司采油工艺研究院 Pipe fisher capable of washing and filtering sand
CN201024941Y (en) * 2007-04-04 2008-02-20 大港油田集团有限责任公司 Sifting tube suspender
CN202745784U (en) * 2012-07-26 2013-02-20 中国石油天然气股份有限公司 Slip type gas lift fishing tool for downhole choke
CN103470229A (en) * 2013-09-24 2013-12-25 山东大学 Sand protection matching pipe string for high-throughput sand filter pipe
CN104213888A (en) * 2014-07-28 2014-12-17 中国石油化工股份有限公司 Down-hole steam injection string of thick-oil thermal production well
CN104481491A (en) * 2014-12-09 2015-04-01 中国石油集团川庆钻探工程有限公司 Circulation control type casing sliding sleeve closing tool
CN106555574A (en) * 2015-09-25 2017-04-05 中国石油化工股份有限公司 Sand control, steam injection integrated apparatus and method
CN207485415U (en) * 2017-11-10 2018-06-12 中国石油化工股份有限公司 A kind of thermal production well steam injection, lost circulation prevention anti-flushing well and production integration tubing string

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